Relay Runtime

Relay Runtime is the core runtime library for building GraphQL-driven applications with the Relay framework, developed by Facebook. Current stable version is 21.0.1, released bi-weekly alongside the Relay compiler. It provides client-side GraphQL execution, data fetching, caching with normalized stores, and reactivity. Key differentiators: strong type safety via generated TypeScript types, declarative data fetching with fragments, and optimized batching. Supports React and other JS frameworks. Ships TypeScript definitions natively.